Injection molding method for thin-wall plastic part

Abstract

The invention provides an injection molding method for a thin-wall plastic part. The injection molding method comprises the following steps of putting plastic raw materials into a hopper, conducting high-temperature melting on the raw materials through a screw extruder, and injecting the raw materials into a mold cavity, wherein the injection pressure ranges from 1500 kg / cm<2> to 3000 kg / cm<2>, injection time is 0.5-2 seconds, and the injection speed is controlled to be 500-1000 mm / s; controlling the temperature of a mold to change dynamically between 50 DEG C and 220 DEG C, and conducting local heating on areas, 0.1-1 mm away from the surface of the mold cavity, of the mold through a high-frequency or ultrahigh-frequency electro-magnetic induction coil, wherein the frequency is controlled to be 100-500 kHz; implementing a pressure maintaining process, wherein the maintained pressure is controlled to be 400-800 kg / cm<2>, and pressure maintaining time is 4-10 seconds; lowering the temperature of the mold, so that the temperature of the mold reaches the ejection temperature of plastic melt or below, wherein the cooling time is controlled to be 4-10 seconds; and implementing a mold opening process, so that the molded plastic part is ejected. By means of the injection molding method for the thin-wall plastic part, cooling time of the mold can be effectively shortened, and energy waste can be reduced.

Description

technical field [0001] The invention relates to the field of injection molding, in particular to an injection molding method for thin-walled plastic parts. Background technique [0002] With the advent of the mobile Internet era, people's pursuit of "light, thin, small, and smart" smart devices has formed a trend, which has led to the rapid development of thin-wall injection molding. At present, there is no uniform definition of thin-wall injection molding. From the aspect of wall thickness of plastic parts, injection molding with wall thickness less than 1mm or 1.5mm is usually defined as thin-wall injection molding; from the flow length ratio (that is, from the melt into the mold to the melt In terms of the ratio of the flow length of the farthest point of the cavity that the body must fill to the corresponding average wall thickness), injection molding with a flow length ratio of 100 or 150 or more is defined as thin-wall injection molding. With the development of techno...

AI Technical Summary

Problems solved by technology

[0014] In order to overcome the problems of injection molding of thin-walled plastic parts in the prior art, due to the small circulation channel, the condensation on the surface of the mold affects the uniform injection of the melt and the warping of the finished product.

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